This is the Bat-Hex kit with 3mm Bottom Plate (carbon only).

• Please note that the mid arms and braces may be not robust enouph for had crash. 
• FC, ESC, VTX mounting holes: 25.5x25.5mm(Front only), 20x20mm, 16x16 (front and rear), M2
• Motor mounting holes: 9x9mm, M2
• Standoff mounting holes spacing: Front=18mm, Rear=14mm; M2
• Prop size: 2"(flat), 2.5"-3"(front and rear props should be pusher)
• Thickness: bottom=3mm, top=1.5mm
• Weight: About 24g
• Betaflight Motors Mixer: HEX X

The front standoff mounting holes are suitable for using "Diatone ROMA F1 Camera Metal Protector" for a Nano size camera. For that purpose, the rear standoff height should be 20mm.

https://www.diatone.us/collections/roma-acc/products/diatone-roma?variant=39321176637527

The following picture shows my 3" light weight build with Diatone ROMA F1 Camera Protector. This frame is a prototype and is not the same as the product.

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